Oral examinations, whether for students or those in the work place, can be quite stressful, but they do not have to be.
Preparation in advance with your English Language Coach, can make such a difference both to your confidence and your understanding of the topic(s) you are going to be expected to discuss. If you are already familiar and comfortable in discussing the topic in an ‘external’ environment, then you will have the confidence necessary ‘on the day’ of the examination.